Pillow fighting is a popular nighttime event for school trips and road trips alike. But in one part of Japan, pillow fighting is steadily becoming something far too serious.

In Ito hot springs - a well known hot springs spot near Tokyo - an All-Japan pillow fighting competition is held.

Why would pillow fighting work as a competition? It's odd, yet the rules are pretty well set.

Know your pillow fighting rule

First thing you have to know is the starting position. Everyone must begin from a futon, "sleeping". Obviously, no competitor is asleep: they are only pretending. They are waiting for the fight to begin.

Once the fight commences, competitors start throwing pillows at each other. Even small details are not missed in the rules: for example, if a pillow hit two opponents, only the first-contact opponent gets dropped out of the fight.

There is also a strange rule called "teacher's coming". The game seems to emulate a school-trip situation, so you have to lie down and stay quiet when teachers are around. In addition, the boss of the side who used the "teacher's coming" rule is able to move around for 10 seconds.

We asked the person in charge of the competition

It's such an odd yet interesting game, so we decided to ask Kawanishi, who is a PR staff of the Ito Tourism Association

This game started from an idea by a high school student. As it was an interesting idea, we held the first event on February 2013.

A pretty simple history.

At the first event, only 6 teams participated, but that grew by 8 times by the fourth event (held in 2016). We were surprised that people from all around the country - including Hokkaido up north and Kagoshima down south. If you are confident about your pillow throwing skills, we challenge you to our competition.

From a pretty simple beginning, the game had became a fully-fledged national competition.

Although it can be a bit of a stress relief, mature adults can get a little heated when the game gets exciting.

Here's the official video explaining the rules. It's almost 15 minutes long! (In Japanese only, sorry.)